(1) Field of Invention
The subject invention relates to an improved constant velocity joint for transmission of power between two angularly-displaceable shafts. In a typical universal joint or Cardan joint, the velocity or rpm of the input shaft is equal to the velocity or rpm of the output shaft when the two shafts are coaxially aligned. However, when the output shaft is disposed at an angle with respect to the input shaft, the output shaft velocity is not constant or equal to that of the input shaft. In fact, the output velocity or rpm of the output shaft in such a situation is sinusoidal with respect to the velocity or rpm of the input shaft. Vehicles with front-wheel drive require a special front-wheel suspension wherein the front axle contains a constant velocity joint in order to provide flexibility when going over bumps or especially when turning or cornering. Constant velocity joints are used to overcome sinusoidal motion of the output shaft. In other words, the output shaft, which is connected to a front wheel, will rotate at the same velocity or rpm as the input shaft or drive axle no matter what the angle between the output shaft and the drive axle, as in hitting bumps or during turning or cornering.
(2) Description of the Prior Art
Typically, the prior art constant velocity joints provide for the constant transmission of rotary motion between two angularly-displaceable shafts. As is known in the art this is accomplished by constant velocity joints having an outer member and an inner member which are operatively connected by lost motion torque transmitting means. The torque transmitting means is generally comprised of balls in a cage, pivot means projecting transversely from one end of a shaft member, or by rollers mounted in a cup or ball and engaging slots in the other member. Typically, the components of the prior art constant velocity joints have close manufacturing tolerances and must be casted and machined separately and then assembled.
In addition, although typical prior art constant velocity joints compensate for any misalignment of the two rotating shafts, the prior art constant velocity joints do not allow for axial movement between the outer member and the inner member. Lateral or axial movement between the inner member and outer member is particularly desirable in a constant velocity joint when a vehicle is turning or cornering as will be later described in more detail.